Multiple-operation machine assembly



March 20, 1945- I w. K. MILLHQLLAND 2,371,906

MULTIPLE-OPERATION MACHINE /ASSEMB-LY l Filed Feb:` 1l, 1943 3 Sheets-Sheet l nine/ffy;

'March 2o, 1945.

MULTIPLE-OPERATION MACHINE AS SEMBLY Filed Feb. l1, 1943 7mm/frs.

yV.. K. MILLHOLLAND 2,371,906

3 Sheets-Sheet 2 Patented Mar. 20, 1945 UNITED STATES ATENT OFFICE MULTIPLE-OPERATION MACHINE ASSEMBLY 2 Claims.

The fabrication of large and heavy articles, such aslarge bombs, which require a multiplicity o'f eaccurate machining operations, has heretofore involved, as a considerable item. of expense, not

-only the transfer of the article from one vrnachine `to another but alsothe successive-accurate indexing of the article with the successive `manipulative machines, all -of `which is time consuming and expensive and oiers repeated Opporheavy articles requiring accuratemachining may be accomplished at much greater speed-and `at less cost than heretofore.

The accompanying drawings Aillustrate an ernbodiment of my invention.

Fig. V 1 is a perspective View of -an emlaodiment of my invention;

Fig. 2 is a section perspective, on allarger scale, of the work-holder advancing means;

Fig. 3 is a transverse vertical section on a larger scale;

Fig. 4 -a vfragmentary longitudinal' section showing the work-holder advancing means; and

Fig.' 5 is a Ywiring diagram.

I-n the drawings A, B, C, D indicate a Aseries of4 machine tools each capable of automatically performing one Yor more 4of the desired machining operations to which 'the work pieces are to be subjected. In the drawings, 4machines A, B, C are indicated as of the twin type, comprising a bed 110 with two automatic 4machin-ingnifiits `H `-H axially spaced suiciently to permit kwork-holders 'H to 4pass therebetween, While machine v'D Ais a single unit type. Each machining unit I I is actuated by its individual motor I'Z'and comprises an indexing head` I3 slidable axially of the unit and provided with parallel indexing lpins, I4, I4. Machining units of this type are well known in the art (see, for instance, my Patents Nos. 1,841,546 and 1,849,683) and vary in detail according to the operations to be performed. Such units, quite commonly, may be started by the closing of an energizing circuit, whereupon they operate through a cycle and automatically come to rest at their initial position.

The several machines A, B, C,.D (as many as y may be needed) are arranged side-by-side with the spaces between their unit-s II,v Il in a straight-line series and through these spaces is extended a work-holder runway R (comprising parallel tracks I5, I5) which unies the several machines. Runway R is adapted to receive, support, and guide, Va plurality of work-holders H, each `of which comprises .indexing .elements .L6

having ,indexing `pe'riorations I1 ,adapted .to re'- cei-ve Iindexing pins I4.

Each work-holder VH .comprisespuitable -workclamping velements I8, .such ,as the illustrated sliding heads, and .means ,for .clamping them upon, .and releasing them from, the work-,pieces W. .In .thepresent instance .this Lclamping-nieans comprises lthe 4oppositely-threade'd shaft LMl, threaded into nuts 2li `carried .Iby lelements |18., and .provided with a wormqgear 2.1 .meshing with a worm 22 carried by -a ,shaft .2;3 ,journalled in the main body `of holder H ,and .having a :polygonal end 2.3 .by which -it :may :he manipulated Each work-ladder II .is gprovided with `track grooves .24 `to ride upon tracks ifand with ,upwardly .presented shoulders .-25 (Fig. .3) ,parallel with ,grooves 2.4.A

Each machine .bed ALI) is provided with ,a `vertical .iiuidy l,pressure .cylinder Si); :the piston of which carries ,a clamping `par .3I :beneath the opposite .ends of which ythe shoulders .25 may Apass V as the work-,holder traverses ,tracks v-I.5, the arrangement beingsuch that .when ,a work-holder yis in proper yposition Arelative to ,any `one of the machining units fl 1 Aa ,clamp bar-31| maybe torcibly `drawn down upon shoulders 25 -to rmlyhold the work-holder during machining operations performed by the adjacent :unit I|,

Raralleling tracks 1,5, in runway -R,.areftwo grooves ,36, .3B in .each `@of which is ,slidably mounted a feed bar `3l Aprovided' with fa plurality of notches 68 equal -in number to the number of units` A :to -D plus two, these lfbeirig ,adapted to receivepawl-s :3-9 kcarried by the *work-holders I Reed bars 31 Aare reoiprocated (by vpistons 41.0,. MI

of hydraulic cylinders M, 4| mounted in run-I way R.

Each machine bed I8 is provided with a vertically reciprocable spring-biased preliminary-indexing pin 42, the upper end of which is adapted to seat in pockets 43, 43 formed in holders H in such manner as to slightly obstruct, but not prevent, movement of the holders along tracks I5. These preliminary-indexing pins 42 and their cooperating pockets ,43 are so located that they serve to approximately locate the workeholders so that the indexing pins I4 may be projected into `perforations II of the work-holders, for iinal indexing of the work-holders preliminary to 0peration of the machining units II. Each of the units II is provided with .its ownmotor I2 and is of an automatic or semi-automatic type, the devention.

The individual work-pieces W are mounted in individual work-holders H either at a distant point and deposited as a unit on the receiving end of the runway R, and similarly removed as a unit from the discharge end of the runway, or, if desired, clamp operating means, such as hand shaft E equipped with socket 5| to engage end 23', may be provided at the receiving and discharge ends of the runway, as shown in Fig. 1.

As previously stated, my invention contemplates operations on comparatively large workpieces, such as large bombs or housings not easily lifted by hand and consequently, the units A and D will be relatively large and cumbersome requiring considerable floor space if individually operated, but, in accordance with my invention, these large units are placed side-by-side, closely adjacent, with just enough space between to permit necessary movements of the operator (as distinguished from space which would be required if the work were to be individually brought tc and removed from the machining unit). As a consequence, the amount of floor space required for the complete machining operations to be performed on the heavy work-pieces, as well as the time required to complete the `required machining operations, is reduced to a minimum without chance of decrease of accuracy in the finished product.

Whether the initiation of movementsY of units the operations of the clamping bars 3|, and reciprocations of feed bars 37 are all synchronized orV independently accomplished, will be a matter of choice. In any event, the provision of necessary electrical circuits, fluid pressure lines, and controlling valves therefor, is a matter well within present engmeering skill once the general layout, as above described, has been disclosed.

As a suggested system of wiring, Fig. 5 of the drawings is a diagram of appropriate pneumatic, hydraulic, and electrical connections Vfor one pair of units by means of which necessary movements of the vparts of my apparatus may be controlled and synchronized. Each of the units includes an electric motor I2, movement of which serves to automatically project indexing pins I4 to active position and to actuate the machining elements of unit 1|, and fluid pressure means F acting to bias said pins |4 and associate machining elements to at rest positions.

The source P of uid pressure includes a motor MP, a high pressure pump HP connected through valves 5| and pipes 52` with cylinders 30, and a low pressure pump L connected through valve 53 and pipes 54 with cylinders 4|. Closing of switch 5S starts all motors I2 and MP. Closing of switch 55 causes actuation of the feed bars 31 to shift the several work-holders to new positions, whereupon closing of switch 57 starts cycle of operations.

I claim as my invention:

l. A plurality of machine tool units arranged side-by-side and each comprising machining elements movable toward and from a vertical plane intersecting all of said units, a runway arranged parallel with said plane and transversely of said several units and extending beyond the end units, a plurality of work-holders removably and slidably mounted on said runway, means by which the several work-holders on the runway may be simultaneously advanced thereon from one unit to the next unit, cooperating indexing means carried respectively by each work-holder and each machining unit .for registering each work-holder successively with the several machining units, each machine-unit indexing means being movable to cooperative relation with a work-holder prior to engagement of the machine unit with the work carried by the adjacent work-holder, each work-holder being formed, on its under side, to present an upwardly facing surface, means associated with said runway adjacent each Inachining unit and positioned to overlie said surface when a work-holder is indexed with such unit, and means for forcing said last-named means downwardly to clamp such work-holder in position on said runway.

2. A plurality of machine tool units arranged side-by-side and each comprising machining elements movable toward and from a vertical plane intersecting allof said units, a runway arranged parallel with said plane and transversely of said several units and extending beyond the end units, a plurality of work-holders removably and slidably mounted on said runway, means by which the several work-holders `on the runway may be simultaneously advanced thereon from one machining unit to the next succeeding unit, cooperating indexing means carried respectively by each work-holder and each machining unit for registering each work-holder successively with the several machining units, each work-holder being formed on its under side with a pair of oppositely laterally extending grooves opening toward each other, a plate reciprocably mounted between the lateral edges of said runway adjacent each of said machining units, the lateral edges of each of said plates being positioned to enter the said grooves of a work-holder as the same approaches indexing relation with an associated machining unit, and means for forcing said plates downwardly to clamp their engaged work-holders immcvabiy in place on said runway.

WILLIAM K. IWILLHOLLAND. 

